The present invention relates to a mobile device such as a mobile information terminal equipped with a global positioning system (GPS) function.
GPS systems for receiving a radio wave from a satellite and finding the current position of a moving object are being mounted in mobile phones, personal digital assistants (PDA's), and other mobile devices.
Such mobile devices have GPS receivers built in the mobile device units, utilize memory cards or other interfaces, or utilize USB, BlueTooth, or other various interfaces to provide position information to the mobile device units.
GPS receivers utilizing memory cards or other interfaces have built-in memory cards etc. and are used inserted into slots of the mobile device units. Mobile devices utilizing USB's are connected to GPS receivers with built-in USB's by USB cables to provide position information to the units. Mobile devices utilizing radio waves BlueTooth utilize BlueTooth to provide position information.
The above related art suffers from several problems. Mobile devices with GPS receivers built into the mobile device units or utilizing memory cards or other interfaces suffer from the problem that the GPS receivers are susceptible to noise from the mobile device units due to their proximity to the units, so sometimes the performance of the GPS receivers, specifically the sensitivity, position accuracy, or position-finding time, is not sufficient.
Further, mobile devices utilizing memory cards or other interfaces end up with their slots occupied when using the GPS function, so their slots cannot be used for other applications.
In mobile devices utilizing BlueTooth, the GPS receiver and BlueTooth device sides require batteries, so the devices become large in size. Further, when the batteries runs out, these functions can no longer be used. When using these interfaces, it is therefore necessary to mount these interfaces at the mobile device sides.